The Istanbul consensus workshop on embryo assessment: proceedings of an expert meeting

BACKGROUND Many variations in oocyte and embryo grading make inter-laboratory comparisons extremely difficult. This paper reports the proceedings of an international consensus meeting on oocyte and embryo morphology assessment. METHODS Background presentations about current practice were given. RESULTS The expert panel developed a set of consensus points to define the minimum criteria for oocyte and embryo morphology assessment. CONCLUSIONS It is expected that the definition of common terminology and standardization of laboratory practice related to embryo morphology assessment will result in more effective comparisons of treatment outcomes. This document is intended to be referenced as a global consensus to allow standardized reporting of the minimum data set required for the accurate description of embryo development.